1. Field of the Invention
The present invention relates generally to telephone systems and more particularly to a telephone call diverting and answering system having the capability of automatically identifying and assigning telephone calls which have been concentrated onto a reduced number of telephone trunks.
2. Description of the Prior Art
The telephone system provides a vital means of rapid interpersonal communication. Unfortunately, the effectiveness of the basic system is a direct function of the availability of the party being called. To supplement the system a number of telephone call diverting and/or telephone answering systems have been developed. One type of prior art answering system answers incoming telephone calls and delivers a prerecorded taped message. Thereafter, the calling party is provided an opportunity to leave a message which is taped for later review by the called party.
Although providing a great potential, such answering systems have been rather poorly received by callers who, no doubt, resent the impersonal and intimidating nature of such systems. Additionally, it is felt that these systems project a rather poor business image. And, of course, such systems are incapable of selectively processing priority calls.
A more human touch is provided by telephone answering services or bureaus. In one implementation, the answering bureau is directly connected to each of its customer's telephone lines such that ringing occurs at both locations. Typically, the bureau is instructed to answer all telephone calls which the called party does not answer promptly, e.g., within three rings. Since the profitability of most answering bureaus is predicated upon having many customers, this implementation requires that the bureau have an equally large number of dedicated lines. The lines are connected, typically in groups of 80 to 100, to individual switchboards and each switchboard is monitored by a bureau operator.
Besides the obvious expense involved in maintaining a large number of dedicated lines, this implementation is not cost effective in terms of bureau staff. At most times, an individual operator is required to monitor each switchboard. At slack times the individual operators do not have a great deal of activity and thus their time is not sufficiently productive. However, at peak activity time periods, the same operators may be unable to properly count the number of rings of individual calls and then properly answer all of the incoming calls. Further, it is very difficult for an operator on one switchboard with few calls to assist another operator on another switchboard who is unable to handle a sudden flurry of calls on that particular operator's board.
A form of telephone call diverting, referred to as "telephone call forwarding," is provided by some telephone companies in geographic areas in which the company employs electronic signal switching (ESS). A person with this service can cause future incoming telephone calls to be diverted automatically to a telephone set at a different location of that person's choice. For example, this location may be where the person plans to be or even to a telephone answering bureau.
The use of telephone call forwarding to forward calls to an answering bureau would be attractive to the bureau in that it could greatly reduce the number of lines required by the bureau. In addition, the reduced number of lines could each be connected to a number of key-type telephone sets permitting better bureau staffing and sharing of the call load.
Unfortunately, without more, such a reduction in the number of lines would be at the expense of the quality of service offered to the answering bureau's clients. For one thing, telephone call forwarding requires that the user, the bureau's client, properly switch the system over to call forwarding and back to normal operation. More important, since a few lines would be used to handle the calls of all of the bureau's numerous clients, the bureau would lose the ability to identify for which client a particular call is intended. Thus, the bureau could no longer answer each call in the personal manner in which its clients would, such as "Doctor Jones' office". The bureau operator would be forced to guess or ask calling parties who they are calling.
A system for telephone call diverting and answering which addresses these problems is disclosed in the United States Pat. No. 4,117,270 issued to Ronald A. Lesea, one of the present inventors. The system includes a number of telephone call diverters located upon the premises of the various clients of the telephone answering bureau, and one or more telephone call diverter controller/decoders located on the bureau's premises. Each of the call diverters requires two telephone lines, the first of which it monitors for incoming telephone calls. Until such a call is received, the call diverter remains in an idle mode.
When a call diverter detects a ringing signal generated by the telephone company upon the first line, the call diverter signals on off-hook condition on the second line by conducting an off-hook current between the tip and ring line thereof. It then monitors the second line to detect a dial tone signal generated thereon by the telephone company. Upon detecting such a signal, the call diverter pulses the line in such a manner as to dial the telephone number of the answering bureau. Thereafter, it repetitiously generates an identification signal upon the line.
The identification signal represents a unique three-digit code assigned to the respective client. The signal is generated a digit at a time using the standard two-of-seven tone code used for dual tone multi-frequency dialing. After each group of three digits has been transmitted and before the group is repeated, the call diverter briefly monitors the line for a connect-type handshake signal, i.e., the two-of-seven code signal which represents the "*" symbol. It should be noted that until such a handshake signal is detected by the call diverter, the call diverter does not signal an off-hook condition on the first line. Thus, the telephone company continues to generate the ringing signal on the first line, and the calling party is not apprised of the above-described activity.
Upon detection of the above-mentioned handshake signal, the call diverter causes transmission of the identification signal, signals an off-hook condition on the first line and bridges the two lines coupling audio signals therebetween.
Thereafter, the call diverter monitors both lines for dial tone signal and for a disconnect handshake signal, i.e., the two-of-seven code signal which represents the "#" symbol. Upon detection of either signal or after a thirty-minute period has elapsed, the call diverter signals an on-hook condition on both lines and returns to the idle mode.
The one or more call diverter controller/decoders, that are located at the answering bureau's premises, may be connected to respective telephone sets or telephone key sets such that they monitor whatever line the operator selects. When properly connected, and when an operator selects a line upon which a call is being diverted by an above-mentioned call diverter, both the operator and the call diverter controller/decoder receive the three-digit identification code signal transmitted by the call diverter. The call diverter controller/decoder decodes the identification signal and displays the three-digit code which the operator may use to identify the client for which the respective call is intended. When ready, the operator can cause the connect-type handshake signal to be generated, either by depressing the appropriate key on the call diverter controller/decoder or the "*" key on the telephone set, and greet the caller in the appropriate fashion, such as, "Dr. Jones' office."
As can be seen, the above-described prior art system enables telephone answering bureaus to greatly reduce the number of telephone lines which must be maintained and associated employee expenses, while retaining the ability to properly greet clients' callers. Additionally, this system provides a degree of flexibility in that any operator can answer any call.
Although providing improvement over other prior art telephone call diverting and answering systems, the system of U.S. Pat. No. 4,117,270 lacks a degree of desirable automation. The system has no provision for counting rings or assigning calls either on a rotational or weighted basis. Also, the disclosed system is incompatible with many of the other systems, such as the electronic signal switching call forwarding. Finally, no means is provided for automatically obtaining statistics with respect to answered calls.
Though not prior art in itself, a telephone call concentrator is disclosed in the Institute of Electrical and Electronics Engineers, Inc. (IEEE), "Transactions on Communications," Volume COM-27, Number 7, of July 1979, on pages 973-978 which may be of interest.